Antidepressant use and hyperactive delirium at the end of life: retrospective study

Objectives: Little is known about the adverse effects associated with antidepressant use in palliative care inpatients imminently approaching death. This study investigates the relationship between antidepressant use and hyperactive delirium in this population. Methods: This is a retrospective medical record review of patients who died in a metropolitan palliative care unit in Victoria, Australia, during 2019. Generalised estimating equations were used to estimate the association between antidepressant use and presence of hyperactive delirium in the final 2 weeks of life. Results: Of the 501 adult patients who died in the 12-month period, 113 (22.55%) were on at least one antidepressant at the time of admission. Any antidepressant use in the last 14 days of life was significantly associated with the diagnosis of hyperactive delirium (OR 1.48; 95% CI 1.30, 1.68). Patients prescribed antidepressants also experienced longer durations of delirium (3.89 days; SD 4.23) compared with those not taking any antidepressant (2.99 days; SD 3.70) in the final 2 weeks of life. Conclusion: Antidepressant use or discontinuation is significantly associated with hyperactive delirium within 14 days of death. Although the causes of delirium are multifactorial and complex, antidepressant use is a potentially modifiable risk factor.